Comparison of symbolic and ordinary powers of parity binomial edge ideals

In this paper, we investigate when symbolic and ordinary powers of the parity binomial edge ideal of a graph fail to be equal. It turns out that if $${\mathcal {I}}_{G}$$ is the parity binomial edge ideal of a graph G, then in each of the following cases the symbolic power $${\mathcal {I}}_{G}^{(t)}$$ and the ordinary power $${\mathcal {I}}_{G}^t$$ are not equal for some t: (i) the clique number of G is greater than 3; (ii) G has a net; or (iii) G has a PT as an induced subgraph.